Question

Find mean median and mode

No.of plants. 0-2. 2-4. 4-6. 6-8. 8-10. 10-12. 12-14

No.Of houses 1. 2. 1. 5. 6. 2. 3

Answer 1

Soln:

Let us find class marks (xi­) = (upper class limit + lower class limit)/2

Now we may compute xi and fixi as following.

Number of plants	Number of house (fi)	xi	Fixi
0 – 2	1	1	1
2 – 4	2	3	6
4 – 6	1	5	5
6 – 8	5	7	35
8 – 10	6	9	54
10 – 12	2	11	22
12 – 14	3	13	39
Total	N = 20		Sum = 162

From the table we may observe that

N = 20

Sum = 162

Mean ¯¯¯x = Sum/N

162/20 = 8.1

So mean number of plants per house is 8.1

We have used for the direct method values Xi and fi are very small